The invention relates to a heat exchanger, in particular for motor vehicles, for a first gaseous flow medium and a second gaseous flow medium. Said heat exchanger comprises a tube bundle containing a plurality of tubes, a first tube base and a second tube base, a housing, in addition to an inlet connection and an outlet connection for the gaseous medium. The tubes comprise tube ends, which are held and sealed by the tube bases and the housing is connected on one side to the tube bases, forming a cooling chamber for the liquid flow medium and on its end face to the inlet and outlet connections.